Oxygen electrode and temperature sensor

Abstract

A small oxygen electrode and a method of bonding a fluorine resin film are disclosed. This small oxygen electrode includes a flat electrode substrate having at least two electrodes (a working electrode and a counter electrode) formed thereon, and a container substrate having dents formed to confront the two electrodes and contain an electrolyte therein. The container substrate is bonded to the flat electrode substrate, so that the dent confronting the electrode constituting the working electrode has a through hole extending to the side opposite to the flat electrode substrate and a gas-permeable film is formed to cover the through hole. By using this dent structure, the preparation of an oxygen electrode can be conducted while maintaining a wafer form throughout the process, and formation of an electrode pattern can be facilitated. The method of bonding the fluorine resin film includes treating the fluorine resin film with an agent containing metallic sodium, then treating the fluorine resin film with a silane coupling agent. The treated fluorine resin film is fusion bonded by heating, and if necessary, conducting subsequent treatments in vacuo. By adopting this method, the fluorine resin film can be bonded tightly to the substrate and peeling of the fluorine resin film from the substrate can be prevented.

We claim: 
     
       1. A complex sensor including an oxygen sensor and a temperature sensor, comprising: first and second substrates directly bonded to each other, the bonded first and second substrates having a first section for an oxygen sensor and a second section for a temperature sensor, the first and second sections being separated from each other,   a) the first section further comprising: at least two electrodes including a working electrode and a counter electrode, formed on the first substrate,   at least one dent formed on the second substrate and confronting the two electrodes, for storing an electrolyte, the dent confronting the electrode constituting the working electrode having a through-hole extending to the side opposite to the first substrate, and   a gas permeable film formed on the second substrate and covering the through-hole, and     b) the second section further comprising: a thin film resistor formed between the first and second substrates.     
     
     
       2. A complex sensor according to claim 1, wherein an enzyme- or microorganism-immobilized film is provided on the gas permeable film, so that the oxygen sensor acts as a biosensor. 
     
     
       3. A complex sensor including an oxygen sensor, a temperature sensor and a pH sensor, comprising: first and second substrates directly bonded to each other, the bonded first and second substrates having a first section for an oxygen sensor, a second section for a temperature sensor and a third section for a pH sensor, the first, second and third sections being separated from each other,   a) the first section further comprising: at least two electrodes including a working electrode and a counter electrode, formed on the first substrate,   at least one dent formed on the second substrate and confronting the two electrodes, for storing an electrolyte, the dent confronting the electrode constituting the working electrode having a through-hole extending to the side opposite to the first substrate, and   a gas permeable film formed on the second substrate and covering the through-hole,     b) the second section further comprising: a thin film resistor formed between the first and second substrates, and     c) the third section further comprising: a reference electrode formed on the first substrate,   a dent formed on the second substrate and confronting the reference electrode for storing an electrolyte, the dent piercing the second substrate at at least a part of the dent, and   a glass film formed on the second substrate and covering the pierced part of the hole, the glass film being hydrogen ion selective.     
     
     
       4. A complex sensor according to claim 3, wherein an enzyme- or microorganism-immobilized film is provided on the gas permeable film so that the oxygen sensor acts as a biosensor. 
     
     
       5. A complex sensor comprising first and second substrates bonded to each other, the bonded first and second substrates having a first section for an oxygen sensor and a second section for a temperature sensor. 
     
     
       6. A complex sensor according to claim 5, wherein said first and second substrates further include a third section for a pH sensor.